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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
#include "mozilla/dom/MIDIPermissionRequest.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/MIDIAccessManager.h"
#include "mozilla/dom/MIDIOptionsBinding.h"
#include "mozilla/ipc/BackgroundChild.h"
#include "mozilla/ipc/PBackgroundChild.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/RandomNum.h"
#include "mozilla/StaticPrefs_dom.h"
#include "nsIGlobalObject.h"
#include "mozilla/Preferences.h"
#include "nsContentUtils.h"
//-------------------------------------------------
// MIDI Permission Requests
//-------------------------------------------------
using namespace mozilla::dom;
NS_IMPL_CYCLE_COLLECTION_INHERITED(MIDIPermissionRequest,
ContentPermissionRequestBase, mPromise)
NS_IMPL_QUERY_INTERFACE_CYCLE_COLLECTION_INHERITED(MIDIPermissionRequest,
ContentPermissionRequestBase,
nsIRunnable)
NS_IMPL_ADDREF_INHERITED(MIDIPermissionRequest, ContentPermissionRequestBase)
NS_IMPL_RELEASE_INHERITED(MIDIPermissionRequest, ContentPermissionRequestBase)
MIDIPermissionRequest::MIDIPermissionRequest(nsPIDOMWindowInner* aWindow,
Promise* aPromise,
const MIDIOptions& aOptions)
: ContentPermissionRequestBase(
aWindow->GetDoc()->NodePrincipal(), aWindow,
""_ns, // We check prefs in a custom way here
"midi"_ns),
mPromise(aPromise),
mNeedsSysex(aOptions.mSysex) {
MOZ_ASSERT(aWindow);
MOZ_ASSERT(aPromise, "aPromise should not be null!");
MOZ_ASSERT(aWindow->GetDoc());
mPrincipal = aWindow->GetDoc()->NodePrincipal();
MOZ_ASSERT(mPrincipal);
}
NS_IMETHODIMP
MIDIPermissionRequest::GetTypes(nsIArray** aTypes) {
NS_ENSURE_ARG_POINTER(aTypes);
nsTArray<nsString> options;
// The previous implementation made no differences between midi and
// midi-sysex. The check on the SitePermsAddonProvider pref should be removed
// at the same time as the old implementation.
if (mNeedsSysex || !StaticPrefs::dom_sitepermsaddon_provider_enabled()) {
options.AppendElement(u"sysex"_ns);
}
return nsContentPermissionUtils::CreatePermissionArray(mType, options,
aTypes);
}
NS_IMETHODIMP
MIDIPermissionRequest::Cancel() {
mCancelTimer = nullptr;
if (StaticPrefs::dom_sitepermsaddon_provider_enabled()) {
mPromise->MaybeRejectWithSecurityError(
"WebMIDI requires a site permission add-on to activate");
} else {
// This message is used for the initial XPIProvider-based implementation
// of Site Permissions.
mPromise->MaybeRejectWithSecurityError(
"WebMIDI requires a site permission add-on to activate — see "
"site-permission-add-on/ for details.");
}
return NS_OK;
}
NS_IMETHODIMP
MIDIPermissionRequest::Allow(JS::Handle<JS::Value> aChoices) {
MOZ_ASSERT(aChoices.isUndefined());
MIDIAccessManager* mgr = MIDIAccessManager::Get();
mgr->CreateMIDIAccess(mWindow, mNeedsSysex, mPromise);
return NS_OK;
}
NS_IMETHODIMP
MIDIPermissionRequest::Run() {
// If the testing flag is true, skip dialog
if (Preferences::GetBool("midi.prompt.testing", false)) {
bool allow =
Preferences::GetBool("media.navigator.permission.disabled", false);
if (allow) {
Allow(JS::UndefinedHandleValue);
} else {
Cancel();
}
return NS_OK;
}
nsCString permName = "midi"_ns;
// The previous implementation made no differences between midi and
// midi-sysex. The check on the SitePermsAddonProvider pref should be removed
// at the same time as the old implementation.
if (mNeedsSysex || !StaticPrefs::dom_sitepermsaddon_provider_enabled()) {
permName.Append("-sysex");
}
// First, check for an explicit allow/deny. Note that we want to support
// granting a permission on the base domain and then using it on a subdomain,
// which is why we use the non-"Exact" variants of these APIs. See bug
// 1757218.
if (nsContentUtils::IsSitePermAllow(mPrincipal, permName)) {
Allow(JS::UndefinedHandleValue);
return NS_OK;
}
if (nsContentUtils::IsSitePermDeny(mPrincipal, permName)) {
CancelWithRandomizedDelay();
return NS_OK;
}
// If the add-on is not installed, and sitepermsaddon provider not enabled,
// auto-deny (except for localhost).
if (StaticPrefs::dom_webmidi_gated() &&
!StaticPrefs::dom_sitepermsaddon_provider_enabled() &&
!nsContentUtils::HasSitePerm(mPrincipal, permName) &&
!mPrincipal->GetIsLoopbackHost()) {
CancelWithRandomizedDelay();
return NS_OK;
}
// If sitepermsaddon provider is enabled and user denied install,
// auto-deny (except for localhost, where we use a regular permission flow).
if (StaticPrefs::dom_sitepermsaddon_provider_enabled() &&
nsContentUtils::IsSitePermDeny(mPrincipal, "install"_ns) &&
!mPrincipal->GetIsLoopbackHost()) {
CancelWithRandomizedDelay();
return NS_OK;
}
// Before we bother the user with a prompt, see if they have any devices. If
// they don't, just report denial.
MOZ_ASSERT(NS_IsMainThread());
mozilla::ipc::PBackgroundChild* actor =
mozilla::ipc::BackgroundChild::GetOrCreateForCurrentThread();
if (NS_WARN_IF(!actor)) {
return NS_ERROR_FAILURE;
}
RefPtr<MIDIPermissionRequest> self = this;
actor->SendHasMIDIDevice(
[=](bool aHasDevices) {
MOZ_ASSERT(NS_IsMainThread());
if (aHasDevices) {
self->DoPrompt();
} else {
nsContentUtils::ReportToConsoleNonLocalized(
u"Silently denying site request for MIDI access because no devices were detected. You may need to restart your browser after connecting a new device."_ns,
nsIScriptError::infoFlag, "WebMIDI"_ns, mWindow->GetDoc());
self->CancelWithRandomizedDelay();
}
},
[=](auto) { self->CancelWithRandomizedDelay(); });
return NS_OK;
}
// If the user has no MIDI devices, we automatically deny the request. To
// prevent sites from using timing attack to discern the existence of MIDI
// devices, we instrument silent denials with a randomized delay between 3
// and 13 seconds, which is intended to model the time the user might spend
// considering a prompt before denying it.
//
// Note that we set the random component of the delay to zero in automation
// to avoid unnecessarily increasing test end-to-end time.
void MIDIPermissionRequest::CancelWithRandomizedDelay() {
MOZ_ASSERT(NS_IsMainThread());
uint32_t baseDelayMS = 3 * 1000;
uint32_t randomDelayMS =
xpc::IsInAutomation() ? 0 : RandomUint64OrDie() % (10 * 1000);
auto delay = TimeDuration::FromMilliseconds(baseDelayMS + randomDelayMS);
RefPtr<MIDIPermissionRequest> self = this;
NS_NewTimerWithCallback(
getter_AddRefs(mCancelTimer), [=](auto) { self->Cancel(); }, delay,
nsITimer::TYPE_ONE_SHOT, __func__);
}
nsresult MIDIPermissionRequest::DoPrompt() {
if (NS_FAILED(nsContentPermissionUtils::AskPermission(this, mWindow))) {
Cancel();
return NS_ERROR_FAILURE;
}
return NS_OK;
}